[ubuntu-havana-R1.06-50] ECMP: instance cleanup failed after deleting SI

In ECMP regression we are seeing cleanup failure. We have test which launches 8 instance in a SI.
When we delete SI after test, few instance are not deleted and still have reference to service instance.

Can you please take a look at below setup.

CFGM : [u'nodea35', u'nodea34']
Control Nodes : [u'nodea35', u'nodec53']
Compute Nodes : [u'nodec54', u'nodec55', u'nodec56']
Collector : [u'nodea35', u'nodec53']
WebUI : nodec53
OpenstackUI : nodea34

Logs:

root@nodea35:~/logs/0000_#curl http://127.0.0.1:8095/virtual-machine/01121ba2-5000-41c6-b1a9-15e068eaf91b | python -m json.tool
.
.
"service_instance_refs": [ { "attr": null, "href": "http://127.0.0.1:8095/service-instance/bd54034d-ae76-4768-8013-ec376c8e54b8", "to": [ "ERROR" ], "uuid": "bd54034d-ae76-4768-8013-ec376c8e54b8"
 } ],

.
.

root@nodea35:~/logs/0000_# curl http://127.0.0.1:8095/service-instances | python -m json.tool | more % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent
 Left Speed 100 25 100 25 0 0 7916 0 --:--:-- --:--:-- --:--:-- 12500 { "service-instances": [] } root@nodea35:~/logs/0000_#